Periscope and the like.



J. W. HASSELKUS.

museum AND THE LIKE.

APPLICATION FILED MAY'18, 1912.

Patented Mar. 9, 1915.

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J. W. HASSELKUS. PBBISGOPB AND THE LIKE. APPLICATION FILED my 13, 1912.

Patented Mar. 9, 1915.

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INVENTOR ELKUS m Iris fim nel s Winn sans Parana r JOHN WILLIAMHASSELK'US, OF CLAPHAM COMMON, LONDON, ENGLAND, ASSIGNOB T0 BOSS.LIMITED, OF CLAPHAIVI COMMON, LONDON, ENGLAND.

PERISCOPE -AND THE LIKE.

Application filed May 18, 1912.

To all whom it may concern:

Be it known that T, JOHN WiLLIAM Has- SELKUS, a subject of the King ofGreat Britain and Ireland, of 3 North Side, Clapham Common, in thecounty of London, England, have invented new and useful Improvements inPeriscopes and the like, of which the following is a specification.

This invention relates to periscopes and the like of the type shown inmy Patent 1,047,051, dated Dec. 10, 1912.

The present invention has for its object, aside from an improved lenssystem, to increase the brilliancy of the image by lessening the amountof glass through which the image-forming rays must pass.

In the accompanying drawings, Figure 1 is a longitudinal section on theline AB, Fig. 2, of the upper portion of the instrument; Fig. 2 is aplan with the cover 22 of the prism combination of the auxiliary opticalsystem removed; and Fig. 3 is a cross section through the upger mainprism.

The prism combination 21 here shown reverses the image from one hand tothe other (say right to left) and causes the emerging rays, (indicatedby the dotted lines) to leave the said combination at an angle of 90 orthereabout, to their original direction, the necessary reversal of theimage in a vertical direction being produced by the lower main prism(not shown, but marked 5 in Patent 1,047,051 above mentioned), of theinstrument. The lens combination 21 may be secured in position in anysuitable way, as by a spring 2% pressing thereon.

To increase the illumination, whether in an instrument according to theaforesaid U. S. Letters Patent No. 1,0&7,051, dated Dec. 10, 1912, or inone improved as hereinbefore described, I omit the special prism (marked14 in the drawings of the specification of the aforesaid U. S. LettersPatent No. 1,0a7 ,051, dated Dec. 10, 1912, cemented to the hypote-Specification of Letters Patent.

Patented Mar. 9, 1915.

Serial No. 698,235.

nuse of the upper main prism l and to enable the rays from the auxiliaryoptical system to pass unhindered, or practically unhindered, to theobject glass 2 of the main telescope, I omit, or cut away, a portion ofthe upper prism 1, which may be done for instance by boring a hole ofthe required diameter through the prism, or (as shown in theaccompanying drawing) by cutting a slot 25 from the edge toward themiddle of the said prism, until the required aperture is obtained. Theouter parts of the instrument are, or may be, like those of theaforesaid U. S. Letters Patent No. 1,047,051, dated Dec. 10, 1912, andrequire no description or further illustration here.

What I claim is 1. In a periscope, a main sighting aperture and a mainprism for deflecting the image therefrom, in combination with anauxiliary sighting aperture and an auxiliary deflecting prism fordeflecting the image therefrom, said main prism being apertured topermit the unimpeded passage therethrough of the image from theauxiliary de fleeting prism system to the main system, substantially asdescribed.

2. In a periscope having a main sighting aperture, a prism fordeflecting the image therefrom, an auxiliary sighting aperture and meansfor deflecting the image from the latter through the main deflectingprism, the latter being apertured to permit the unimpeded passagetherethrough of the image from the auxiliary sighting aperture,substantially as described.

In testimony whereof I have signed my name to this specification in thepresence of two subscribing witnesses.

JOHN WILLIAM HASSELKUS.

Witnesses:

J. H. RICHMOND, C. M. MoGILoHmsT.

Copies of this patent may be obtained for five cents each, by addressingthe Commissioner of Patents,

Washington, D. G.

